Let's find out how much tax was paid. Subtract the amounts: 1800 - 1683 = 117
So $117 was paid in tax. Divide this over the initial amount 1800 and we get 117/1800 = 0.065
To convert from decimal form to percent form, you multiply by 100. This is basically moving the decimal point 2 spots to the right. So we go from 0.065 to 6.5%
Therefore the answer is 6.5%